Report on the 21st International Symposium on Geo‑disaster reduction, 5–8 August 2023, Shanghai, China

Abstract The joint event of 21st International Symposium on Geo-disaster Reduction (21st ISGdR) was held onsite and online during 5–8 August 2023 in Shanghai, China. This symposium focused on the theme of “A new era for safe and resilient coastal and marine systems”, providing a platform for academics, researchers and practitioners from different countries to discuss the research progress and exchange ideas on the reduction of disasters. The symposium consisted of keynote lecture, invited lectures and other presentations in parallel session.